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It seems that i have another project in my month old bought X3. It's near the 100,000 mark and I bought it with 98k. I have been pleased with it but I have come to the conclusion that the previous owner did not do any or most recommended maintenance.

Fortunately, this has not damage any major parts or components but this car needs to last me a while so I am the lucky one that must deal with it.

So, as one of the previous threads indicate, I replaced the coolant tank expansion because of a leak. It turns out, however, that the leak was actually the top radiator hose which I immediately fixed and that was resolved. In any event, I am happy that the coolant system has no leak, but another issue was spotted: oil leak near the driver side which hinted at the OFHG, and the mechanic pretty much confirmed that it was.

Now, I have done extensive research and have a pretty good idea of everything that must be done but I had some specific questions for those of you that have done it before I decided to do this myself:

Fan: Many DIY's have the fan removed but it's the mechanical one. I have an electric one, must it be removed?

Alternator: So it has to be definitely removed. My question is the tensioner itself, is it just a matter of getting a torx set and removing it? I'll try looking for other DIY's where the belts are manipulated to see if I can get a better picture.

P/S Pump: Some of the DIY's I have seen talk about removing the pump and some don't. I believe that's because of the slight differences in engines and models but can anyone answer this question with certainty as it pertains to a 2004 BMW X3 3.0 with the M54 Engine?

VANOS System: A majority of people also talk about replacing VANOS oil lines, washers, and even hex bolts. Is that recommended for an X3? I think at the very least, maybe the washers should be changed... but I'd love to hear your thoughts.

RTV Sealant: Yes - or - No? I think I want to add a slight line of it but I wanted to hear specific experiences from those of you that have done this. I was thinking of using this sealant RTV Black Permatex

Torque for bolts: I am pretty set on tighten the bolts to 22 nm. thoughts?

Other leaks: I have read from at least half a dozen people of either continuing leaks or other somewhat major issues happening. I'd love to hear anything negative that has occurred to X3 owners on this.

Thank you all again, I look forward to hearing what your responses would be even if it answers one point asked above.

It seems that i have another project in my month old bought X3. It's near the 100,000 mark and I bought it with 98k. I have been pleased with it but I have come to the conclusion that the previous owner did not do any or most recommended maintenance.

Fortunately, this has not damage any major parts or components but this car needs to last me a while so I am the lucky one that must deal with it.

So, as one of the previous threads indicate, I replaced the coolant tank expansion because of a leak. It turns out, however, that the leak was actually the top radiator hose which I immediately fixed and that was resolved. In any event, I am happy that the coolant system has no leak, but another issue was spotted: oil leak near the driver side which hinted at the OFHG, and the mechanic pretty much confirmed that it was.

Now, I have done extensive research and have a pretty good idea of everything that must be done but I had some specific questions for those of you that have done it before I decided to do this myself:

Fan: Many DIY's have the fan removed but it's the mechanical one. I have an electric one, must it be removed?

Alternator: So it has to be definitely removed. My question is the tensioner itself, is it just a matter of getting a torx set and removing it? I'll try looking for other DIY's where the belts are manipulated to see if I can get a better picture.

P/S Pump: Some of the DIY's I have seen talk about removing the pump and some don't. I believe that's because of the slight differences in engines and models but can anyone answer this question with certainty as it pertains to a 2004 BMW X3 3.0 with the M54 Engine?

VANOS System: A majority of people also talk about replacing VANOS oil lines, washers, and even hex bolts. Is that recommended for an X3? I think at the very least, maybe the washers should be changed... but I'd love to hear your thoughts.

RTV Sealant: Yes - or - No? I think I want to add a slight line of it but I wanted to hear specific experiences from those of you that have done this. I was thinking of using this sealant RTV Black Permatex

Torque for bolts: I am pretty set on tighten the bolts to 22 nm. thoughts?

Other leaks: I have read from at least half a dozen people of either continuing leaks or other somewhat major issues happening. I'd love to hear anything negative that has occurred to X3 owners on this.

Thank you all again, I look forward to hearing what your responses would be even if it answers one point asked above.

- a.c.

I just finished replacing the OFH gasket last week on my 2005 X3.

* You do not have to remove the fan, but it does give you more room and is very simple to remove. One bolt, one push pin fastener and 2 electrical connectors.

* A T-50 driver is used to relieve tension on the tensioner. You turn it clockwise to relieve tension. It is held on by 2 13mm head bolts.

* The PS pump definitely needed to be removed. It is held on by 2 16mm head bolts. They are different lengths, so make sure they go back on the same way they came off.

* I removed the front VANOS oil line from the VANOS and left the rear one on the OFH housing. You should replace the washers if you remove the bolt. No reason to remove the bolt.

* I would not recommend RTV in this case. It really isn't meant for this type of gasket. It is more useful on flat paper type gaskets.

* 22 Nm is correct for the OFH bolts. Again, they are different lengths, so keep track of which came from where.

* I also had a leak in the back corner of the Valve Cover Gasket. At 114K miles, I was surprised that the spark plug well gaskets had turned completely brittle. It definitely was time for renewal.